2017 YAMAHA YS125 brake

Table of contentsSafety information ............................ 1-1
Description ....................................... 2-1
Left view ......................................... 2-1
Right view ....................................... 2-2
Controls and instruments ............... 2-3
Instrument an d control functions ... 3-1
Main switch/steering lock............... 3-1
Indicator lights and warning light ............................................. 3-2
Multi-function meter unit ................ 3-3
Handlebar switches ........................ 3-5
Clutch lever .................................... 3-6
Shift pedal ...................................... 3-6
Brake lever...................................... 3-7
Brake pedal .................................... 3-7
Fuel tank cap .................................. 3-8
Fuel ................................................. 3-8
Catalytic converters ..................... 3-10
Seat .............................................. 3-11
Adjusting the shock absorber assemblies ................................ 3-11
Sidestand ..................................... 3-12
Ignition circuit cut-off system ....... 3-13 For your safety – pre-operation
checks
............................................... 4-1
Operation an d important ri din g
points ................................................. 5-1
Starting the engine .......................... 5-1
Shifting ............................................ 5-2
Tips for reducing fuel consumption ................................ 5-3
Engine break-in ............................... 5-3
Parking ............................................ 5-4
Perio dic maintenance an d
a d justment ........................................ 6-1
Owner’s tool kit ............................... 6-2
Periodic maintenance chart for the emission control system .............. 6-3
General maintenance and lubrication chart ........................... 6-4
Removing and installing the
cowling and panels ...................... 6-8
Checking the spark plug ............... 6-10
Engine oil and oil filter element ..... 6-11
Cleaning the air filter element and cleaning the check hose ............ 6-14
Adjusting the engine idling
speed ......................................... 6-16
Checking the throttle grip free play ............................................ 6-16
Valve clearance ............................. 6-17
Tires .............................................. 6-17 Cast wheels .................................. 6-19
Adjusting the clutch lever free
play ............................................ 6-19
Checking the brake lever free play ............................................ 6-20
Adjusting the brake pedal free play ............................................ 6-21
Brake light switches ..................... 6-21
Checking the front brake pads
and rear brake shoes ............... 6-22
Checking the brake fluid level ...... 6-22
Changing the brake fluid ............. 6-23
Drive chain slack........................... 6-24
Cleaning and lubricating the
drive chain ................................. 6-25
Checking and lubricating the cables ........................................ 6-26
Checking and lubricating the throttle grip and cable ............... 6-26
Checking and lubricating the
brake and shift pedals............... 6-26
Checking and lubricating the brake and clutch levers ............. 6-27
Checking and lubricating the centerstand and sidestand........ 6-28
Lubricating the swingarm
pivots......................................... 6-28
Checking the front fork ................. 6-29
Checking the steering................... 6-29
Checking the wheel bearings ....... 6-30
Battery .......................................... 6-30UBT4E0E0.book Page 1 Thursday, November 17, 2016 10:55 AM

Table of contents
Replacing the fuse.........................6-31
Replacing the headlight bulb.........6-33
Replacing the auxiliary light
bulb ...........................................6-34
Replacing the brake/tail light
bulb ............................................6-35
Replacing a turn signal light bulb ............................................6-35
Replacing the license plate light bulb ............................................6-36
Front wheel....................................6-36
Rear wheel.....................................6-37
Troubleshooting ............................6-39
Troubleshooting chart ...................6-41
Motorcycle care an d stora ge ..........7-1
Matte color caution .........................7-1
Care .................................................7-1
Storage ............................................7-3
Specifications ....................................8-1
Consumer information .....................9-1
Identification numbers .....................9-1
Diagnostic connector ......................9-2
Vehicle data recording ....................9-2
In dex ................................................10-1
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Description
2-1
2
EAU10411
Left view
4
7
1
2
8
9
3
6
5
10
1. Auxiliary light (page 6-34)
2. Headlight (page 6-33)
3. Fuel tank cap (page 3-8)
4. Idle adjusting screw (page 6-16)
5. Air filter element (page 6-14)
6. Seat (page 3-11)
7. Shock absorber assembly spring preload adjusting ring (page 3-11)
8. Brake/tail light (page 6-35) 9. License plate light (page 6-36)
10.Shift pedal (page 3-6)
UBT4E0E0.book Page 1 Thursday, November 17, 2016 10:55 AM

Description
2-2
2
EAU10421
Right view
3,4
1
2
5
6
7
8
9
1. Shock absorber assembly spring preload adjusting ring (page 3-11)
2. Owner’s tool kit (page 6-2)
3. Battery (page 6-30)
4. Fuses (page 6-31)
5. Engine oil filter element (page 6-11)
6. Engine oil drain bolt (page 6-11)
7. Engine oil filler cap (page 6-11)
8. Brake pedal (page 3-7) 9. Rear brake light switch (page 6-21)UBT4E0E0.book Page 2 Thursday, November 17, 2016 10:55 AM

Description
2-3
2
EAU10431
Controls and instruments
12 34 678
5
1. Clutch lever (page 3-6)
2. Left handlebar switches (page 3-5)
3. Main switch/steering lock (page 3-1)
4. Multi-function meter unit (page 3-3)
5. Front brake fluid reservoir (page 6-22)
6. Right handlebar switch (page 3-5)
7. Throttle grip (page 6-16)
8. Brake lever (page 3-7)
UBT4E0E0.book Page 3 Thursday, November 17, 2016 10:55 AM

Instrument and control functions
3-7
3
EAU78900
Brake leverThe brake lever is located on the right
side of the handlebar. To apply the
front brake, pull the lever toward the
throttle grip.
This model is equipped with a unified
brake system.
When the brake lever is pulled, the rear
brake is also applied proportionally to
the front brake. For full braking perfor-
mance, operate the brake lever and
brake pedal simultaneously.TIP Because the unified brake system
is mechanical, additional free play
can be felt in the brake pedal when the brake lever is being
pulled, but this does not indicate a
malfunction.
 The unified brake system does not
operate when the brake pedal is
pressed down directly.
EAU78910
Brake ped alThe brake pedal is located on the right
side of the motorcycle. To apply the
rear brake, press down on the brake
pedal.TIPBecause the unified brake system is
mechanical, additional free play can be
felt in the brake pedal when the brake
lever is being pulled, but this does not
indicate a malfunction.
1. Brake lever
1
1. Brake pedal
1
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For your safety – pre-operation checks
4-1
4
EAU15599
Inspect your vehicle each time you use it to make sure the vehicle is in safe operating condition. Always follow the inspection
and maintenance procedures and schedules described in the Owner’s Manual.
WARNING
EWA11152
Failure to inspect or maintain the vehicle properly increases the possibility of an acci dent or equipment damag e.
Do not operate the vehicle if you fin d any pro blem. If a pro blem cannot be corrected b y the proce dures provi ded in
this manual, have the vehicle inspecte d b y a Yamaha dealer.Before using this vehicle, check the following points:
ITEM CHECKS PAGE
Fuel • Check fuel level in fuel tank.
• Refuel if necessary.
• Check fuel line for leakage. 3-8
En gine oil • Check oil level in engine.
• If necessary, add recommended oil to specified level.
• Check vehicle for oil leakage. 6-11
Front brake • Check operation.
• If soft or spongy, have Yamaha dealer bleed hydraulic system.
• Check brake pads for wear.
• Replace if necessary.
• Check fluid level in reservoir.
• If necessary, add specified brake fluid to specified level.
• Check hydraulic system for leakage. 6-22, 6-22
Rear brake • Check operation.
• Check pedal free play.
• Adjust if necessary. 6-21, 6-22
Clutch • Check operation.
• Lubricate cable if necessary.
• Check lever free play.
• Adjust if necessary. 6-19
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For your safety – pre-operation checks
4-2
4
Throttle grip • Make sure that operation is smooth.
• Check throttle grip free play.
• If necessary, have Yamaha dealer adjust throttle grip free play and lubricate ca-
ble and grip housing. 6-16, 6-26
Control ca bles • Make sure that operation is smooth.
• Lubricate if necessary.
6-26
Drive chain • Check chain slack.
• Adjust if necessary.
• Check chain condition.
• Lubricate if necessary. 6-24, 6-25
Wheels an d tires • Check for damage.
• Check tire condition and tread depth.
• Check air pressure.
• Correct if necessary. 6-17, 6-19
Brake an d shift pe dals • Make sure that operation is smooth.
• Lubricate pedal pivoting points if necessary.
6-26
Brake an d clutch levers • Make sure that operation is smooth.
• Lubricate lever pivoting points if necessary. 6-27
Centerstan d, si destan d • Make sure that operation is smooth.
• Lubricate pivots if necessary. 6-28
Chassis fasteners • Make sure that all nuts, bolts and screws are properly tightened.
• Tighten if necessary.
—
Instruments, li ghts, si gnals
an d switches • Check operation.
• Correct if necessary.
—
Si destan d switch • Check operation of ignition circuit cut-off system.
• If system is not working correctly, have Yamaha dealer check vehicle. 3-12
ITEM CHECKS PAGE
UBT4E0E0.book Page 2 Thursday, November 17, 2016 10:55 AM